$(function(){
    
   var active_link = 'design';

   $('.services_link').click(function(){
       var link = $(this).attr('id').split('services_').join('').split('_link').join('');

       if ( link != active_link ) {
           $(this).html('<img src="images/services_'+ link +'_link_over.png" />');
           $('#services_' + link + '_content').css('display', 'block');
           active_link = link;
       }

       $('.services_link').each(function(){
           var link = $(this).attr('id').split('_link').join('');
           if ( link != active_link ) {
               $(this).html('<img src="images/services_'+ link +'_link.png" />');
           }
       })

       $('.services_content').each(function(){
           var content = $(this).attr('id').split('services_').join('').split('_content').join('');

           if ( content != active_link ) {
               $(this).css('display', 'none');
           }

       });
   });
    
});